Minor tweaks to entirePlanX resolvers to support updated REST API

[briri]

Description

Part of #261

• Added versionedTemplate schema and resolver so we can fetch a versioned template by its id.
• Switched entirePlan schema, resolvers and service to use versionedXId instead of xId (e.g. use versionedTemplates instead of Templates)
• Updated entirePlan service to use the default MemberRole when none is provided

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

REST API calls are working with switch to call entirePlan resolvers. I've done some limited testing, I'm sure there will be bugs that surface as we begin using and testing. I will

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I updated the CHANGELOG.md and added documentation if necessary
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[jupiter007]

Looks good. I didn't see any updates to the CHANGELOG.md file though